1. Field of the Invention
The present invention relates to novel platinum complexes of glycolic acid type which have antitumor activity comparable to or more potent than that of cisplatin. The nephrotoxicity is very low and the water solubility is high.
2. Description of the Prior Art
Compounds analogous to cisplatin [U.S. Pat. Nos. 3,892,790 and 3,904,663] have intensively been investigated since its potent antitumor activity was observed; as the result of the fact, compounds such as malonato(1,2-diaminocyclohexane)platinum(II) [U.S. Pat. No. 4,169,846], sulfato(1,2-diaminocyclohexane)platinum(II) [U.S. Pat. Nos. 4,200,583 and 4,256,652], 4-carboxyphthalato(1,2-diaminocyclohexane)platinum(II) [British Patent Publication No. 2,003,468], cis-dichloro-trans-dihydroxy-bis(isopropylamine)platinum(IV) [U.S. Pat. No. 4,394,319], and the like are known presently.
The present inventors have also been studying compounds analogous to cisplatin and prepared various new types of platinum complexes having potent antitumor activity and high water solubility, for example, novel platinum complexes [British Patent Publication No. 2,091,731], and the like.